package com.example.broadcasttest;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

import android.widget.Toast;

public class MainActivity extends AppCompatActivity {



    private IntentFilter intentFilter;

    private NetworkChangeReceiver networkChangeReceiver;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        intentFilter = new IntentFilter();
        intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
        networkChangeReceiver = new NetworkChangeReceiver();
        registerReceiver(networkChangeReceiver, intentFilter);

    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
    unregisterReceiver(networkChangeReceiver);

    }



    class NetworkChangeReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {
            ConnectivityManager connectionManager = (ConnectivityManager)
                    getSystemService(Context.CONNECTIVITY_SERVICE);
            NetworkInfo networkInfo = connectionManager.getActiveNetworkInfo();
            if (networkInfo != null && networkInfo.isAvailable()) {
                Toast.makeText(context, "network is available",
                        Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(context, "network is unavailable",
                        Toast.LENGTH_SHORT).show();
            }

        }

    }

}
